From 69c4bfbfab9d4a2cb29064c718ef40a039bee724 Mon Sep 17 00:00:00 2001
From: MatMoul <matmoul@gmail.com>
Date: Sat, 25 Apr 2026 03:41:01 +0200
Subject: [PATCH] fix: preserve stack until operation completes

---
 src/rpn-calculator.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/rpn-calculator.js b/src/rpn-calculator.js
index 106eed2..27a6055 100644
--- a/src/rpn-calculator.js
+++ b/src/rpn-calculator.js
@@ -369,9 +369,13 @@ class RpnCalculator {
       throw new Error('Stack underflow');
     }
 
-    const operands = argCount > 0 ? this.stack.splice(0, argCount).reverse() : [];
+    const operands = argCount > 0 ? this.stack.slice(0, argCount).reverse() : [];
     const result = operation.execute(this, ...operands, ...args);
 
+    if (argCount > 0) {
+      this.stack.splice(0, argCount);
+    }
+
     if (Array.isArray(result)) {
       for (let i = result.length - 1; i >= 0; i -= 1) {
         this.push(result[i]);